What happened to these 30 carbine cases?

A situation that perhaps our M1 carbine gurus will diagnose easily - but which I find a bit puzzling.

Today I fired 30 test rounds of 30C - reloads all using new (unfired, anyway) LC brass, 14.8g of H110, and 3 brands of SR primers - Tula, Wolf, and CCI. All worked just fine. I wanted to see how the brass - untrimmed, but under 1.290 after resizing and expansion - and the various primers worked. I also wanted to see if a larger charge (I used 14.5g of H110 or a bit less in my first 30C reloads) brought the point of impact up a bit @ 50 and 100yds (it did).

Then for comparison, practice, and fun, I fired about 30 S&B factory rounds (before switching over to my Mosin Nagant to continue my epic struggle to determine whether I do in fact have to move the front sight about .001" to the right to center the hits @ 100yds - and to happily fire a Garand that the shooter next to me graciously offered to share).

Of those, about a third showed a distinctive dent in the case mouth when I recovered them. I hope the photos here show what I'm talking about.

Each and every LC case was fine (that is, no real distortions or dents to the case mouths). A few questions:

1) what would cause this dent in the case mouths?
2) why some, and not others?
3) why was the LC brass unaffected?

I know (well, I think I know) that the S&B factory might be a little under-powered compared to my reloads. But I can't come up with how that fact might cause 1/3 of the cases to be dented on extraction/ejection.

One more question - can I salvage these cases by bending the case mouths back out to (approx.) round, or do they go in the scrap can?

Footnote: the nearby Garand shooter, happily, didn't want his brass, so now I have a start on my stock of 30-06 cases to feed my recently arrived CMP 1955 HRA Service Grade M1, now undergoing stock cleaning. And there were also scads of .223 cases I happily scooped up to add to my can of that caliber, which I plan to clean and sell.

If you enjoyed reading about "What happened to these 30 carbine cases?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!

FROGO207

June 22, 2012, 06:40 AM

What you are seeing is the brass hitting somewhere on the rifle when ejected. It might be more power or might be less causing the brass to bounce off the top or bottom of the ejection port. Probably low power allowing the front of the case to bounce off side of the receiver near the back of the barrel. It is no big deal other than the need to bend out the case mouths when reusing the brass. FWIW I have saved brass that has been crushed lots worse so no worries IMHO. Using the proper propellant charge for the weight bullet to get a good speed of ejection impulse to smoothly eject the brass will make the problem a non issue. Just takes a bit of experimentation to achieve usually. As always if things get worse over time on any recoil operated firearm check the recoil buffer for wear and replace if necessary.

USSR

June 22, 2012, 07:27 AM

I agree with FROGO207's assessment. Get yourself some sort of round tapered tool to tap into the case neck and remove the "ding". You will likely need it for your Garand anyways. I use a knife sharpener.

Don

cfullgraf

June 22, 2012, 09:31 AM

I frequently use a pair of needle nose pliers to round out cases. I just leave the jaws closed and put the nose of the pliers in the case mouth to iron it out.

Also, you can spread the jaws a little while in the case to help push the dent out.

The round outside of the jaws work well at getting the case mouth expanded out back to near round.

I have both a miniature and standard pair of pliers and use the one appropriate for the task.

Then, the resize die will finish the job and get the mouth round again.

blarby

June 22, 2012, 09:36 AM

A resize pin will fix this without any intervention.

rcmodel

June 22, 2012, 11:30 AM

+1
The cases do a double back flip out of the rifle on ejection and hit the receiver or bolt handle.
Look for tiny little brass tracks on the bolt handle or receiver and you will see where.

That ain't nothing to worry about.
They will be straight after you resize them.
And for sure after you expand them.

rc

16in50calNavalRifle

June 22, 2012, 12:14 PM

Thanks all for your help. I did suspect it was the charge and the ejection process - trying to think if I have seen any/much of this before when I shot factory ammo (incl. S&B). Since most of the factory cases and all of the "new" LC brass was fine, I'm not going to worry about it.

Already decided to try and load my 30C right at the original 15g level - carbine has a front sight that seems high and shoots low, even lower with less than max. loads, the larger charge seemed to resolve that yesterday (I am reluctant to get into grinding down the front sight blade). I have had a handful of stovepipes with some earlier reloads, and the full/standard load should probably take care of both that and these dents.

Good to hear about fixing the dents. I tried that on a few 45ACP and 9mm cases in my initial loading runs, but did not have great success. Need to find the right tool for the job.

USSR

June 22, 2012, 01:46 PM

16in50calNavalRifle,

Get a simple knife sharpening steel like shown below. Note how it tapers at the point which allows you to insert it a dinged neck, and then give it a slight whack on the handle with the palm of your hand and, voila, instant round neck!!!

Don - thanks. Just looked and sure enough I have one of those in the kitchen. Will give it a try when I do my next 30C run (still waiting for Lee to return my expander die body, which was putting those scratches on the cases). After that, I'll look into how to use the thing to, uh ..... sharpen knives! I have a fairly nifty knife sharpener thinggy I use for sharpening, but really should inform myself on how to use that steel.

realbuffdriver

June 24, 2012, 11:14 AM

My experience with S&B carbine ammo is that it's a bit hotter than the loads that I have worked up. I've also experienced case mouth "dings" with 45ACP ammo that was loaded hotter. That's almost surely the issue.

I bought 1000 rounds of S&B when it was $8.50 per box. Wish I had bought a lot more. It's accurate and the cases reload very nicely.

Best of luck with your carbine reloading!

hang fire

June 25, 2012, 01:29 AM

S&B does load a bit hot sometimes, may just be burning rate of powder they use. I noticed it with my 6.5x55 Swede when shooting 2900+ fps, 131 grain S&B in it. Though accurate, I opted to not shoot the remaining 17 rounds.

16in50calNavalRifle

June 25, 2012, 02:28 AM

Thanks for the input guys. The data I've seen for S&B does not indicate greater velocity than USGI - but I don't have a chrono yet so I don't know what my USGI "duplicate" loads are doing (actually @ 14.8g of H110 there's still some room for .2g more, which is what I will try next).

S&B ammo has always performed well for me - but as a reloader now, I AM a bit wary of their tight primer pockets (at least in 9mm). I segregate the S&B cases (darn thoughtful of them to splash that red laquer on the primers, makes it easy to pick them out of the pile) for now and hope to use them some day after reaming out the pockets a bit .... but that "some day" will probably be a ways off, as I'm unlikely to go to that trouble until I've worked through my nice stock of other 9mm brass.

Hacker15E

June 25, 2012, 08:03 AM

Why are you 'wary' of tight primer pockets?

Just because of the pain of swiping a reamer through them?

moxie

June 25, 2012, 09:05 AM

16in50,

As recommended by others above, please just resize and expand before you use pliers or other means to bend the brass. Those dents are minor and should disappear in the sizing and expanding process.

TonyT

June 25, 2012, 09:10 AM

I agree with MOXIE. Just resize and expand the cses, do not attempt to bend the brass with pliers or other contrivances.

Carl N. Brown

June 25, 2012, 09:55 AM

I don't reload .30 carbine much, may be 200 or 300 rounds since 2001, but when I do I use the case mouth flaring tool from my .32 revolver reloading kit, because a percentage of casings will show a dent on the mouth. I always assumed they had impacted the concrete at the range. In fact, since they went to an asphalt surface I have noticed fewer dents when I sort the brass by manufacturer after decapping, saving the brass for when it will pay to reload.

If you enjoyed reading about "What happened to these 30 carbine cases?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!